I implemented delegates in D

[maik klein via Digitalmars-d]

On Thursday, 9 June 2016 at 21:32:33 UTC, Alex Parrill wrote:
> On Thursday, 9 June 2016 at 21:02:26 UTC, maik klein wrote:
>> Has this been done before?
>
> Well, yes, the entire point of delegates is to be able to 
> capture variables (as opposed to function pointers, which 
> cannot).
>
>
> auto createADelegate(int captured) {
> 	return (int a) => captured + a;
> }
>
> void main() {
> 	auto dg1 = createADelegate(5);
> 	auto dg2 = createADelegate(32);
> 	assert(dg1(5) == 10);
> 	assert(dg1(10) == 15);
> 	assert(dg2(8) == 40);
> 	assert(dg2(32) == 64);
> }
>
> https://dpaste.dzfl.pl/90ebc29651f6
>
> (Unfortunately template delegates, like the ones used with map, 
> don't keep their captured variables alive after the captured 
> variables go out of scope, but it doesn't sound like you need 
> those)

I meant, "has this been implement as a library before". I am well 
aware that delegates exist in the language but as far as I know 
you can not do manual allocation with delegates (to avoid the GC).